STT 231 Exam 1: Foundational Statistics -
Terms & Complete Definitions (Newest
2026/2027 Update) Questions and Verified
Answers | 100% Correct | Grade A
This STT 231 Exam 1 is a 110+ Q&A, it focuses on foundational statistics, covering
data types (qualitative/quantitative), sampling methods, experimental design
(control, randomization, replication), and exploratory data analysis (mean, median,
standard deviation, shape, and outliers). Key concepts include distinguishing
populations (all) from samples (subset), identifying parameters vs. statistics, and
interpreting data visualizations,
Key Exam 1 Terms and Concepts
Population: The entire group of individuals or instances about which we hope to
learn.
Sample: A subset of the population from which data is actually collected.
Parameter: A numerical summary of a population (e.g., population
mean population proportion
Statistic: A numerical summary of a sample (e.g., sample mean sample proportion
Qualitative (Categorical) Data: Data consisting of attributes, labels, or non-
numerical entries (e.g., hair color, car type).
Quantitative (Numerical) Data: Numerical measurements or counts (e.g.,
height, weight, temperature).
Discrete vs. Continuous: Discrete data are countable (0, 1, 2...), while
continuous data can take any value in a range.
Observational Study: Researchers observe and measure characteristics but do
not attempt to influence the subjects.
Experimental Study (Experiment): Researchers apply treatments to subjects
and observe responses.
Key Experimental Design Principles:
Control: Using a control group for comparison to account for confounding factors.
1
, Randomization: Using chance to assign subjects to groups to eliminate bias.
Replication: Repeating the experiment on different subjects to confirm results.
Descriptive Statistics: Organizing, summarizing, and displaying data.
Quiz_________________?
What makes up a data set? -
Answer
Data are made up of observational units (cases)
Quiz_________________?
Variable -
Answer
any characteristic or value recorded for each case; found in columns (vertical)
Quiz_________________?
Observations/Observational Units/Cases -
Answer
Found in rows (horizontal)
Quiz_________________?
Values -
Answer
2
, Items that populate a data set
Quiz_________________?
All variables are either ______ or ______ -
Answer
Categorical or numerical
Quiz_________________?
Categorical Variables -
Answer
Identify a case as a measure of a group, placing each case into exactly one of two
or more groups called levels.
Ex. An MSU student can be classified by their year (first second third...) where
these categories are called levels.
Quiz_________________?
Numerical Variables -
Answer
Measure a numerical quantity for each case. Unlike categorical variables,
numerical operations like adding and averaging make sense for these quantitative
variables.
3
, Ex. we can record how many credits an MSU student has earned (1,2,3...)
Quiz_________________?
Numerical Variables can be divided into two groups: ____ and____ -
Answer
Discrete and continuous
Quiz_________________?
Numerical discrete variables -
Answer
can only take on limited values in a variables domain.
Ex. How many siblings do I have? (1,2,3...) but could not say 1.7 siblings.
Quiz_________________?
Numerical Continuous Variables -
Answer
can take on any value in a variable's domain.
Ex. Height-- could be 52in or 53in or 53.262 in
4
Terms & Complete Definitions (Newest
2026/2027 Update) Questions and Verified
Answers | 100% Correct | Grade A
This STT 231 Exam 1 is a 110+ Q&A, it focuses on foundational statistics, covering
data types (qualitative/quantitative), sampling methods, experimental design
(control, randomization, replication), and exploratory data analysis (mean, median,
standard deviation, shape, and outliers). Key concepts include distinguishing
populations (all) from samples (subset), identifying parameters vs. statistics, and
interpreting data visualizations,
Key Exam 1 Terms and Concepts
Population: The entire group of individuals or instances about which we hope to
learn.
Sample: A subset of the population from which data is actually collected.
Parameter: A numerical summary of a population (e.g., population
mean population proportion
Statistic: A numerical summary of a sample (e.g., sample mean sample proportion
Qualitative (Categorical) Data: Data consisting of attributes, labels, or non-
numerical entries (e.g., hair color, car type).
Quantitative (Numerical) Data: Numerical measurements or counts (e.g.,
height, weight, temperature).
Discrete vs. Continuous: Discrete data are countable (0, 1, 2...), while
continuous data can take any value in a range.
Observational Study: Researchers observe and measure characteristics but do
not attempt to influence the subjects.
Experimental Study (Experiment): Researchers apply treatments to subjects
and observe responses.
Key Experimental Design Principles:
Control: Using a control group for comparison to account for confounding factors.
1
, Randomization: Using chance to assign subjects to groups to eliminate bias.
Replication: Repeating the experiment on different subjects to confirm results.
Descriptive Statistics: Organizing, summarizing, and displaying data.
Quiz_________________?
What makes up a data set? -
Answer
Data are made up of observational units (cases)
Quiz_________________?
Variable -
Answer
any characteristic or value recorded for each case; found in columns (vertical)
Quiz_________________?
Observations/Observational Units/Cases -
Answer
Found in rows (horizontal)
Quiz_________________?
Values -
Answer
2
, Items that populate a data set
Quiz_________________?
All variables are either ______ or ______ -
Answer
Categorical or numerical
Quiz_________________?
Categorical Variables -
Answer
Identify a case as a measure of a group, placing each case into exactly one of two
or more groups called levels.
Ex. An MSU student can be classified by their year (first second third...) where
these categories are called levels.
Quiz_________________?
Numerical Variables -
Answer
Measure a numerical quantity for each case. Unlike categorical variables,
numerical operations like adding and averaging make sense for these quantitative
variables.
3
, Ex. we can record how many credits an MSU student has earned (1,2,3...)
Quiz_________________?
Numerical Variables can be divided into two groups: ____ and____ -
Answer
Discrete and continuous
Quiz_________________?
Numerical discrete variables -
Answer
can only take on limited values in a variables domain.
Ex. How many siblings do I have? (1,2,3...) but could not say 1.7 siblings.
Quiz_________________?
Numerical Continuous Variables -
Answer
can take on any value in a variable's domain.
Ex. Height-- could be 52in or 53in or 53.262 in
4
